CN104105382A - Cooling fin and electric power conversion device comprising same - Google Patents

Abstract

The present invention provides a cooling fin which is not only provided with an air suction port at a right side of the cooling fin, but also additionally provided with a plurality of air suction ports on any side surface in the middle from the right side of the cooling fin to a back side of the cooling fin, and additionally provided with air suction ports on any bottom surface in the middle from the right side of the cooling fin to the back side of the cooling fin, so as to obtain the air newly sucked from the air suction ports between an upstream side and a downstream side of the cooling fin. Air can be sucked from the plurality of air suction ports provided at any side surface or bottom surface in the middle from the right side of the cooling fin to the back side of the cooling fin, therefore, external fresh air is sucked from any position inside the cooling fin, turbulent flow may occur due to collision of two air flow vectors formed by the air from the air suction port at one side towards the back side and the air sucked from the other plurality of air suction ports in the direction perpendicular to the direction of the above-mentioned air.

Description

Heat sink and power conversion device including the heat sink

technical field

The present invention relates to a heat sink and a power conversion device including the heat sink.

Background technique

In general, a power conversion device is composed of the following parts: an input transformer; a plurality of unit inverter units connected to the secondary side of the transformer to form an inverter circuit; Switchboard in closed panel. For example, in the power conversion device described in Patent Document 1 below, the input transformer 4 is housed in the transformer board 1 , and a plurality of (six in the illustrated example) unit inverters arranged in a vertical order are housed in the converter board 2 . In the inverter unit 5 , a control unit 6 and an output cable 7 are housed in the control/output tray 3 .

In addition, the transformer panel 1 and the converter panel 2 are provided with cooling fans 8, 9 on the top of the panel, and the converter panel 2 is introduced into the air inlet 2a-1 with a filter through the front door 2a of the panel. The outside air (cooling air) inside the panel is guided to each inverter unit 5, and the discharged air passes through the wind tunnel 10 formed on the rear side of the panel to the cooling fan 9, and to the cooling fan 9 connected to it. Exhaust ducts (not shown) exit to the outside.

In addition, in the prior art, heat sinks are provided in the inverter unit for air cooling semiconductor modules/elements, and when the heat sink is cooled by forced air cooling, air is sucked in from either side and the air passes through the heat sink. , a structure that discharges warm air from its opposite side faces.

FIG. 1 is a diagram showing the overall structure of a commercially available conventional variable-speed drive conversion table. That is, FIG. 1( a ) is a front view showing the overall structure of the transfer table, and FIG. 1( b ) is a side sectional view viewed from A-A portion showing the overall structure of the transfer table shown in FIG. 1( a ).

As shown in FIGS. 1( a ) and ( b ), a plurality of brackets (not shown) are generally provided on the conversion table 2 , and the unit 3 shown in FIG. 2 is mounted on the brackets. Ventilation fan 1 is placed on the upper surface of conversion table 2 , and a plurality of units 3 are arbitrarily arranged on a bracket inside conversion table 2 .

As shown in FIG. 2 , heat sinks 4 , wind tunnels 5 , semiconductor modules/elements 6 and (cylindrical) capacitors 7 are arranged inside each unit 3 . The ventilation fan 1 starts to work, and the air flow is forced to be generated inside the conversion workbench 2 (the air flow is indicated by the arrow in the figure), and the air flow passing through the ventilation fan 1 is generated through the cooling fin 4 shown in Figure 1(b) and through the wind tunnel 5 . This is a structure for forcibly air-cooling the heat generated by power loss generated during power conversion in the semiconductor module/element 6 in order to obtain a forced air flow, and to escape the heat to the outside.

Fig. 3 is a diagram showing the outline of the airflow inside the unit, Fig. 3(a) is a plan view showing the inside of the unit 3, and Fig. 3(b) is a view showing the structure inside the unit shown in Fig. 3(a) Side sectional view seen from part B-B.

As shown in Figure 3 (a) and (b), arrows indicate that the outside air passing through the air inlet 8 provided on the front side of the heat sink 4 inside the unit 3 passes through the heat sink 4 inside the unit 3 As shown in Fig. 3(b), the temperature of the air on the leeward side (exhaust) is higher than that on the upwind side (intake) compared to the air flow before being discharged from the wind tunnel 5.

In this case, the ventilating fan 1 starts to work, thereby, inside the unit 3, external air is sucked in from the air inlet 8, and it flows into the wind tunnel 5 through the inside of the cooling fin 4, and is exhausted from the wind tunnel 5 to the ventilating fan 1.

Multiple semiconductor modules/elements 6 are disposed on the upper surface of the heat sink 4, the heat generated from the semiconductor modules/elements 6 is transferred to the inside of the heat sink 4 through heat transfer, and the transferred heat is cooled by forced air cooling.

If the forced air cooling of the heat sink 4 is adopted, as shown in FIG. The side (exhaust side) is more likely to be affected by the heat of the upstream side (suction side), and even if it is arranged on the same heat sink 4, there is a problem that a local temperature rise occurs. In addition, depending on the main circuit, variations in the amount of power loss generated during power conversion of the semiconductor module/element 6 occur, and local high temperature locations still occur. The placement of the semiconductor modules/elements 6 and the variation in the amount of power loss that occurs during power conversion are restricted by the connection to the external interface and product specifications, and it is necessary to determine the placement position under these restrictive conditions.

The temperature deviation problem caused by the semiconductor module/element 6 is a local temperature rise. In order to solve this problem, the following countermeasures must be taken: (A) Increase the specification of the ventilation fan 1 installed on the upper surface of the conversion table 2 (increase the overall air volume to increase the wind speed), (B) in order to reduce the thermal resistance of the heat sink 4 and expand the shape and size (increase the contact area with the air).

Taking these countermeasures is indeed effective for parts with high local temperature, but on the other hand, in other parts where the local temperature will not rise, it becomes redundant equipment, and the efficiency of the conversion workbench as a whole is reduced, resulting in an increase in cost and the cost of the entire device. of upsizing.

If it is the forced air cooling method of the existing heat sink, the air in the heat sink is an air flow (laminar flow) with a certain wind speed in a certain direction. The arrangement of semiconductor modules/elements (heating elements) is restricted due to the interface with external components, and it cannot be said that sufficient measures have been taken to prevent the occurrence of local temperature distribution rises on the heat sink. That is, a local temperature rise is ultimately the bottleneck of the thermal problem of the entire device, and the following countermeasures must be taken in order to cool this part.

(a) Improve the specifications of the ventilation fan and increase the absolute amount of air sucked by the heat sink.

(b) Expand the shape of the heat sink to improve heat dissipation.

(c) Change the material of the heat sink to a material with high heat dissipation.

(d) In order to improve the thermal cooling effect of the turbulent flow effect, the shape of the heat sink is made into a complex shape (addition of protrusions to the airflow part in the heat sink).

If the above-mentioned measures (a) to (d) are taken, there is a problem that the cost increases and the size of the entire device increases.

Patent Document 1: Japanese Patent Laid-Open No. 2007-174851 (FIG. 6)

Contents of the invention

Therefore, an object of the present invention is to provide a heat sink capable of reducing the temperature of a specific portion of the heat sink.

In order to solve the above-mentioned problems, the heat sink of the first invention is provided with an air inlet on the front of the unit housing the heat sink, and also has a plurality of air inlets near a portion where the local temperature rises on the side surface of the heat sink.

In addition, in the heat sink according to the second invention, the air intake port is provided on the bottom surface of the unit in which the heat sink is accommodated.

In addition, in the heat radiation fin according to the third invention, a notch is provided in the heat radiation fin, and an inflow portion for introducing fresh air into the heat radiation fin through the notch is formed.

In addition, in the heat sink according to the fourth invention, an adjustment plate for adjusting the air intake amount and the air intake position is provided on the bottom surface of the unit for accommodating the heat sink.

As a result, even in the same heat sink, it is possible to adjust the location where the temperature is to be lowered locally according to the arrangement position of the heat generating element, and also to locally control the wind speed (or air volume) in the heat sink.

In addition, there is no need to install a new air duct, and air cooled in the heat sink can be obtained from a desired location (near the heating element) by providing an air inlet around the heat sink disposed in the existing device.

In addition, according to the suction port adjustment function provided on the bottom surface, the shape of the suction port can be changed to match the component arrangement and the shape of the heat sink, and the compatibility of parts of each product series and product capacity can be maintained.

Description of drawings

FIG. 1 is a diagram showing the overall structure of a conventional variable speed drive conversion table.

FIG. 2 is a diagram showing the configuration of a unit mounted inside the transfer table shown in FIG. 1 .

Fig. 3 is a diagram showing the outline of the air flow inside the unit shown in Fig. 2 .

FIG. 4 is a diagram showing the configuration of a heat sink according to Embodiment 1 of the present invention.

FIG. 5 is a diagram illustrating the action of the heat sink according to Embodiment 1 of the present invention.

6A is a bottom view of a unit incorporating a heat sink according to Embodiment 1 of the present invention.

Fig. 6B is a diagram showing the structure of an adjustment plate according to the embodiment of the present invention, which is attached to the bottom surface of the unit shown in Fig. 6A to adjust the intake air volume and the position of the air intake port.

Fig. 7 is a diagram showing how the adjustment plate is attached according to the embodiment of the present invention.

Fig. 8 is a diagram showing an example of a pattern of an intake port by changing the damper plate according to the embodiment of the present invention.

FIG. 9 is a diagram showing the configuration of a heat sink according to Embodiment 2 of the present invention.

FIG. 10 is a diagram illustrating the action of the heat sink according to Embodiment 2 of the present invention.

Detailed ways

Embodiments of the present invention will be described in detail below.

(implementation mode 1)

FIG. 4 is a diagram showing the configuration of a heat sink according to Embodiment 1 of the present invention. In addition, FIG. 5 is a diagram illustrating the action of the heat sink according to Embodiment 1 of the present invention.

In FIG. 4 and FIG. 5 , the structure of the heat sink according to Embodiment 1 of the present invention is that not only the air inlet on the front side of the heat sink is provided, but also any side or bottom surface in the middle from the front of the heat sink to the back of the heat sink is provided. There are multiple air suction ports on the top, and air can be inhaled from all the air suction ports at the same time.

That is, in Fig. 4 (a), (b) and Fig. 5 (a), (b), on the heat sink 4, not only the air inlet 8 on the front side of the heat sink is provided, but also the front side of the heat sink to the heat dissipation A plurality of air inlets 9 are set on any side in the middle of the back of the sheet, and air inlets 10 are also arranged on any bottom surface from the front of the heat sink to the middle of the back of the heat sink. On the upstream side and the downstream side of the heat sink 4 Obtain the fresh air sucked from air inlet 9 and 10 between.

Therefore, it is also possible to inhale air from the air inlets 9 and 10 on any side or bottom surface of the heat sink 4 from the front to the middle of the back, thereby sucking in external fresh air from any position inside the heat sink 4. Due to the difference in the flow direction of the air, that is, due to the collision of the two air flow vectors of one side of the air from the suction port 8 toward the back side and the air sucked in from the suction ports 9 and 10 in a direction at right angles to it, a The turbulent flow enables air intake without being affected by heat from the upstream side of the air flow inside the heat sink 4 at the portion where the air intake port is disposed.

In this way, in the present embodiment, an air intake port is provided on any side or bottom surface between the front and back of the heat sink 4, thereby generating turbulent flow due to the vector of the air flow sucked in from the outside. The heat sink 4 can use a standard heat sink without increasing the cost, and can greatly reduce the temperature compared with the inside of the existing heat sink. In addition, the air inlets 9 and 10 are added, and the air inlets are provided on any side or bottom surface from the front to the back of the heat sink 4, and a new air flow is created from this position. Reduce the temperature.

In addition, the existing technology for generating turbulent flow is that it is necessary to take countermeasures such as a method of forming the flow surface of the air into unevenness and a method of forming it into a complicated shape so that the air flow becomes random. Forming into a special shape increases the cost.

FIG. 6A is a bottom view of the unit 3 viewed from the bottom surface. On the bottom surface of the unit 3, a hole for a wide inlet and a hole for a narrow inlet are arranged at intervals. In addition, FIG. 6B is a diagram showing the structure of an adjusting plate 11 that can change the size of the hole for the air inlet that is arranged on the bottom surface of FIG. A square hole and two rectangular holes) 12, a slit-shaped sliding hole 13 that enables the adjustment plate 11 to move in the unit 3.

FIG. 7 is a diagram showing a state where the adjustment plate 11 shown in FIG. 6B is attached to the bottom surface of the unit 3 shown in FIG. 6A . In Fig. 7, the adjustment plate 11 shown in Fig. 6B is closely attached to the unit 3 from the bottom surface side, and the sliding hole 13 is fixed at a certain position with the fixing screw 14, so that at this position, the suction port provided on the bottom surface 10 becomes the desired size. If you want to change the position of the adjustment plate 11 to change the size of the suction port 10 arranged on the bottom surface, loosen and move the fixing screw 14, and fix it again at the desired position. In this way, the adjustment plate 11 can be moved in the direction of the thick arrow shown on the right side of FIG. 4 to change the size of the air inlet 10 provided on the bottom surface of the unit 3 . Changing the size of the intake port 10 provided on the bottom surface of the unit 3 means that the amount of external air sucked in through the intake port 10 can be changed.

FIG. 8 is a schematic view showing when the size of the air inlet provided on the bottom surface of the unit 3 is changed. That is, in pattern 1 of FIG. 8 , the first row of fixing screws 14 is fixed at the upper end of the slide hole 13 in the same position as that shown in FIG. 7 . In this case, open about 2/3 of the hole for the narrow air inlet, and about 1/2 of the upper side of the two substantially square holes provided on the adjustment plate 13 for the hole for the wide air inlet. Open left and right.

In the mode 2 of Fig. 8, the first row of fixing screws 14 is fixed at a position slightly lower than the upper end of the sliding hole 13. In this case, the hole for the narrow suction port is completely closed, while for the wide one As for the holes for the air inlet, the two substantially square holes provided in the adjustment plate 13 are fully opened.

In the pattern 3 of FIG. 8, the first row and the second row of fixing screws 14 are fixed at approximately equal positions at the upper end and lower end of the sliding hole 13. In this case, the hole for the narrow suction port is completely closed. , In addition, about the lower side 1/2 of the two substantially square holes provided on the adjustment plate 13 for the hole for the wide air inlet is opened.

In pattern 4 of FIG. 8 , the first row of fixing screws 14 is fixed at approximately the middle of the sliding hole 13. In this case, the hole for the narrow suction port is completely closed, while the wide suction port The holes used are also completely closed. That is, the air intake port provided on the bottom surface of the unit 3 becomes inoperative.

In pattern 5 of FIG. 8 , the first row of fixing screws 14 is fixed at a position slightly lower than the approximate middle of the sliding hole 13 . About 1/2 of the upper side of the two approximately square holes on the top is opened, and the hole for the wide suction port is completely closed by the adjustment plate 13.

In mode 6 of FIG. 8 , the second row of fixing screws 14 is fixed at the lower end of the sliding hole 13 , in this case two roughly square holes on the adjustment plate 11 for the narrow suction hole. The lower side 1/2 of the hole is opened about, and for the hole that the wide suction port is used, open correspondingly according to the size of the two rectangular holes that are arranged on the adjusting plate 11.

In this way, by shifting the position of the adjustment plate 11 along the slide hole 13 at the fastening position of the fixing screw 14, it is possible to change the two approximately square holes and the two rectangular holes provided on the adjustment plate 11, and the The sizes of the narrow holes for the air inlet and the wide holes for the air inlet on the bottom surface of the unit 3 can be freely changed according to the heat dissipation conditions inside the heat sink. That is, it is very important to select the optimum position and shape of the suction port provided on the bottom surface from the above-mentioned various modes according to the position of the part to be cooled and the amount of intake to be sucked. For example, in mode 1, the position of the adjustment plate 11 is set on the front side, and the shape and size of the air inlet provided on the bottom surface become smaller, so it is suitable for local cooling. The shape of the suction port on the bottom surface is enlarged, so the suction volume increases, which is very effective for cooling a wide area.

In addition, as the heat sink, which is not shown in the drawings, well-known types such as plate type, pin type, and hollow heat sink can also be used. When air is sucked from the bottom surface side, the plate-shaped fins (for example, plate-shaped, hollow fins) allow air to flow in from between the fins to inhale air.

(Embodiment 2)

FIG. 9 is a diagram showing the configuration of a heat sink according to Embodiment 2 of the present invention. In addition, FIG. 10 is a diagram illustrating the action of the heat sink according to Embodiment 2 of the present invention.

In Fig. 9 and Fig. 10, the heat sink according to Embodiment 2 of the present invention is the same as the heat sink according to Embodiment 1 of the present invention described above. A plurality of suction ports are newly provided on any side or bottom surface in the middle of the back of the sheet, and air can be sucked from all the suction ports at the same time.

That is, in Fig. 9 (a), (b) and Fig. 10 (a), (b), a plurality of air inlets 9 are provided on any side from the front of the heat sink to the middle of the back of the heat sink, and, A notch is provided in the air inflow part of the heat sink 4, and external air is sucked in from this part. In addition, an air inlet 10 is provided on any bottom surface in the middle from the front of the fin to the rear of the fin. The external air sucked in from the air inlet 10 is sucked into the inside through the notch provided in the heat sink 4 .

In this way, similarly to the heat sink according to Embodiment 1 of the present invention, it is also possible to take in air from the air inlets 9 and 10 provided on any side or bottom surface of the heat sink 4 in the middle from the front to the back. Any part inside the cooling fin 4 sucks in fresh air from the outside. Due to the difference in the direction of the air flow, the air collides with each other, resulting in turbulent flow. Inhale due to the influence of heat. As a result, the temperature can be significantly reduced compared with the inside of the conventional heat sink. In addition, the air inlets 9 and 10 are added, and the air inlets are provided on any side or bottom surface in the middle of the front to the back of the heat sink 4, and a new air flow is created from this position, so the temperature can be lowered without setting an air duct. .

In addition, as the heat sink, a well-known type such as a plate type, a pin type, and a hollow heat sink can be used, similarly to the heat sink according to Embodiment 1 of the present invention described above. As a heat sink, pin-type heat sinks (the heat sinks are not plate-shaped, but the type composed of multiple columns or corner columns) do not need to have the above-mentioned gaps, as long as there are multiple holes on any side from the front to the back of the heat sink. A suction port 9 gets final product.

Claims (10)

1. A heat sink, characterized in that: An air intake is provided on the front of the unit for accommodating the heat sink, and a plurality of air intakes are also provided near the side of the heat sink where the local temperature rises. 2. The heat sink according to claim 1, characterized in that: An air intake port is also provided on the bottom surface of the unit for accommodating the heat sink. 3. The heat sink according to claim 1 or 2, characterized in that: A notch is provided on the heat sink, and an inflow portion for introducing fresh air into the heat sink is formed through the notch. 4. The heat sink according to any one of claims 1 to 3, characterized in that: An adjustment plate for adjusting the suction volume and the position of the suction port is provided on the bottom surface of the unit for accommodating the cooling fins. 5. The heat sink according to claim 4, characterized in that: The adjustment plate is movable on a slit provided parallel to the long side of the unit to change the openings of the plurality of intake ports provided on the bottom surface of the heat sink. 6. The heat sink according to claim 5, characterized in that: There are a plurality of patterns in which the adjustment plate is moved over the slit to change the openings of the plurality of intake ports provided on the bottom surface of the heat sink. 7. The heat sink according to claim 5 or 6, characterized in that: The adjuster plate has a plurality of holes formed in groups at intervals inside the slit according to the outer shape of the heat sink, and the holes have different shapes. 8. The heat sink according to any one of claims 4 to 7, characterized in that: The adjustment plate is temporarily fixed by a temporary fixing member temporarily fixed at a predetermined position of the gap. 9. The heat sink according to claim 8, characterized in that: The temporary fixing member is composed of a plurality of screws that are crimped on the unit to fix the position, and the screws include multiple sets of two. 10. A power conversion device, characterized in that: Comprising the heat sink and conversion workbench described in any one of claims 1 to 9, The heat sink according to any one of claims 1 to 9 is accommodated in a unit and placed on a plurality of brackets of the conversion table, and a ventilation fan is mounted on the upper surface of the conversion table.